Electrical Machines Field weakening control method is used for the _________ ? below rated speed both A and B above rated speed None of these below rated speed both A and B above rated speed None of these ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Brushes are always placed on--------------- , in order to achieve sparkles commutation? either GNA or MNA MNA None of these GNA either GNA or MNA MNA None of these GNA ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A dc shunt generator, when driven without any excitation, showed an open circuit voltage of 12 V. When the field winding was excited, the voltage dropped to zero. It happened because field resistance was higher than critical resistance field winding was wrongly connected there was no residual magnetism in the field circuit there was a break in the armature circuit field resistance was higher than critical resistance field winding was wrongly connected there was no residual magnetism in the field circuit there was a break in the armature circuit ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Two mechanically coupled alternators deliver power at 50 Hz and 60 Hz respectively. The highest speed of the alternators is 3000 rpm. 3600 rpm. 600 rpm. 500 rpm. 3000 rpm. 3600 rpm. 600 rpm. 500 rpm. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Methods of synchronizing of alternator may be done by all bright lamp method. all dark lamp method. one dark two bright. all of these. all bright lamp method. all dark lamp method. one dark two bright. all of these. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Minimum allowable resistivity of power transformer insulating oil is generally taken as 3 X 1012 Ω - cm at 27°C and 0.3 X 1012 2 X 1012 Ω - cm at 27°C and 0.2 X 1012 4 X 1012 Ω - cm at 27°C and 0.4 X 1012 1 X 1012 Ω - cm at 27°C and 0.1 X 1012 3 X 1012 Ω - cm at 27°C and 0.3 X 1012 2 X 1012 Ω - cm at 27°C and 0.2 X 1012 4 X 1012 Ω - cm at 27°C and 0.4 X 1012 1 X 1012 Ω - cm at 27°C and 0.1 X 1012 ANSWER DOWNLOAD EXAMIANS APP